低温胁迫下交替呼吸途径对当归幼苗叶绿素荧光活性的影响

以岷当归幼苗为材料,通过温室盆栽试验研究了在低温(4℃和-7℃)胁迫下交替呼吸途径对当归幼苗叶片叶绿素含量和荧光特性的影响,探讨交替呼吸途径在当归响应低温逆境过程中的作用。结果表明,随着胁迫温度的降低和处理时间的延长,当归叶片的叶绿素含量、实际光化学效率[Y(Ⅱ)]、光合电子传递速率(ETR)及光化学淬灭系数(qL)逐渐降低,而非光化学猝灭系数(NPQ)升高;同时,低温胁迫也导致当归幼苗叶片交替呼吸容量显著升高;在低温胁迫下,经交替呼吸途径抑制剂[1 mmol·L~(-1)的水杨基氧肟酸(SHAM)]预处理的当归幼苗叶片叶绿素含量、Y(Ⅱ)、ETR及qL进一步显著下降,而NPQ进一步显著升高,且温度越低升降幅度越大。研究发现,低温胁迫对当归幼苗叶片叶绿素的合成以及PSⅡ的光化学性能产生了显著抑制,低温胁迫下交替呼吸途径对当归幼苗叶绿素合成以及PSⅡ的光化学性能具有一定的保护作用。     

外源ATP对NaCl胁迫下菜豆叶片叶绿素荧光特性的调节

盐胁迫是影响植物生长的主要逆境因子之一,外源ATP被发现可作为信号分子参与植物对逆境胁迫生理反应的调节。为了探明外源ATP在植物盐胁迫响应中的作用,以增强植物对土壤盐渍化的耐性,更好地应用于土壤盐渍化修复。该研究以菜豆( Phaseolus vulgaris)为材料,通过叶绿素荧光技术探讨了外源ATP 对菜豆叶片在NaCl胁迫下叶绿素荧光特性的变化规律。结果表明：在NaCl胁迫下,叶片光系统Ⅱ( PSⅡ)潜在最大光化学量子效率( Fv/Fm)、光适应下最大光化学效率( Fv′/Fm′)、PSⅡ光适应下实际光化学效率[ Y (Ⅱ)]、光化学荧光猝灭( qP)、电子传递速率( ETR)与对照组相比均有显著性下降,而非光化学猝灭( NPQ)和( qN)较对照组有显著性增加,这表明NaCl胁迫导致菜豆叶片光系统Ⅱ光化学效率的下降和光能耗散的增加。而外源ATP(eATP)的处理能有效缓解NaCl胁迫所造成的Fv/Fm、Fv′/Fm′、Y(Ⅱ)、qP、ETR下降和NPQ、qN的上升。该研究结果表明在NaCl胁迫下外源ATP可以有效地提高菜豆幼苗光系统Ⅱ( PSⅡ)的光化学反应效率。     

硝基苯酚胁迫下外源褪黑素对水稻幼苗生长及生理特性的影响

采用液体培养实验方法,研究硝基苯酚胁迫对水稻(Oryza sativa L.)幼苗生长、抗氧化特性、光系统Ⅱ(PSⅡ)光合特性的影响,以及添加外源褪黑素对缓解硝基苯酚胁迫的作用。结果显示,随着硝基苯酚胁迫浓度的升高,水稻幼苗株高、根长、地下部干重、地上部干重、全株干重和叶片PSⅡ实际光化学效率[Y(Ⅱ)]、光化学淬灭系数(q P)、PSⅡ电子传递速率(ETR)、叶绿素含量均有所下降,而叶片非光化学淬灭系数(qN、NPQ)上升;同时,根系活性氧[过氧化氢(H_2O_2)和超氧阴离子(O·-2)]积累量、抗氧化酶[超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)]活性,以及渗透调节物质(可溶性蛋白和可溶性糖)含量呈先升高后降低的趋势。在非硝基苯酚胁迫下,与对照组相比,添加外源褪黑素显著提高了幼苗地下部干重、根系可溶性糖含量和SOD活性、叶片PSⅡ光化学效率和叶绿素含量。与单独添加硝基苯酚处理相比,硝基苯酚+褪黑素复合处理显著缓解了硝基苯酚胁迫对幼苗生长、叶片PSⅡ光化学效率和叶绿素合成的抑制作用;降低了根系活性氧水平、抗氧化酶活性和渗透调节物质含量。研究结果表明添加外源褪黑素能够显著缓解硝基苯酚胁迫对水稻幼苗生长、根系活性氧水平、抗氧化酶活性、叶片PSⅡ光化学效率及叶绿素合成的不良影响,提高水稻幼苗对硝基苯酚胁迫的适应性。     

珙桐苗木叶片光合特性对土壤干旱胁迫的响应

通过控制土壤含水量,研究了土壤干旱胁迫对2年生珙桐(Davidia involucrata Baill.)幼苗叶面积、叶绿素含量、光合作用及叶绿素荧光参数的影响,以探讨珙桐光合作用对土壤干旱胁迫的响应机理.结果表明,干旱胁迫后,珙桐叶片失水脱落,各干旱胁迫处理叶面积比对照显著降低23%～98%,但单位面积的叶绿素含量却无显著变化;干旱处理的珙桐幼苗净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、水分利用效率(WUE)显著低于对照(P<0.05);干旱胁迫对珙桐幼苗叶片的初始荧光产量(F0)及最大荧光产量(Fm)没有产生显著影响,却显著降低了PSⅡ最大光化学量子产量(Fv/Fm)、PSⅡ实际光化学量子产量(Yield)、电子传递速率(ETR)及光化学淬灭系数(qP),使非光化学淬灭系数(qN)显著升高(P<0.05).研究发现,土壤水分亏缺对珙桐叶片的光合系统造成了不可逆的伤害,严重抑制了其正常的光合作用和生长发育;珙桐幼苗对土壤干旱胁迫极为敏感.     

重金属对盐生草光合生理生长特性的影响

以盐生草幼苗为试验材料,分别设置0(CK)、50、100、200、400μg?g-1的Ni2+、Cu2+处理,研究重金属Ni2+和Cu2+对盐生草光合生理特性的影响.结果表明:盐生草叶片光合色素含量、净光合速率(Pn)、气孔导度Gs、蒸腾速率Tr、PSⅡ最大光化学效率Fv/Fm、非光化学猝灭系数qN及生长指标(株高、地上部干重和鲜重)在50μg?g-1的Ni2+处理时均达到最大值,后随Ni2+浓度继续增加,其叶片叶绿素a、叶绿素b、Pn、Gs、Tr、Fv/Fm、PSⅡ电子传递量子产率ΦPSⅡ、光化学猝灭系数qP、qN及各项生长指标逐步下降并低于对照水平,而细胞间隙CO2浓度(Ci)较对照呈增加趋势.在50μg?g-1的Cu2+处理时,盐生草叶片光合色素含量、Pn、Gs、Tr、Ci、Fv/Fm、ΦPSⅡ、qP、qN及各项生长指标均达峰值;在100μg?g-1Cu2+处理时,光合色素含量、Pn、Gs、Tr、Fv/Fm、ΦPSⅡ、qN及各项生长指标较对照仍有增加,而后随Cu2+浓度继续增加,其叶绿素a、叶绿素b、各光合参数、叶绿素荧光参数及生长指标均逐步降低并低于对照.可见,盐生草Pn在Ni2+胁迫下的下降主要是由非气孔限制所致,而Cu2+胁迫下的下降主要是由气孔限制所致;低浓度Ni2+和Cu2+对盐生草生长具有一定促进作用,过高浓度Ni2+和Cu2+则会通过抑制盐生草叶片叶绿素合成,影响其光合作用,从而抑制植株生长.     

渗透胁迫对小麦幼苗叶绿素荧光参数的影响

用叶绿素荧光诱导动力学技术,研究模拟干旱条件对小麦幼苗叶片叶绿素荧光参数,即原初光能转化效率(F_v/F_m)、光合电子传递量子效率(φPSⅡ)、qP(光化学猝灭)、qNP(非光化学猝灭)、ETR(表观光合量子传递效率)的影响.结果表明,渗透胁迫对小麦幼苗叶绿素荧光参数影响较大.随着渗透胁迫的加剧,F_v/F_m和F_v/F_o都表现出现降低-增加-降低的趋势,在渗透胁迫2 h以前,小麦叶片内部没有发生光抑制,但随着胁迫的加剧,F_v/F_m值增加,使得小麦幼苗叶内发生光抑,导致ΦPSⅡ和ETR的下降;在渗透胁迫过程中,小麦叶片吸收光能的光化学猝灭(qP)的下降和光化学猝灭(qNP)呈现先降低后增加的趋势,说明小麦在受到干旱胁迫前期,PSⅡ反应中心的开放比例降低;在胁迫2h后,随着胁迫的加剧,qP和qNP增加有利于提高PSⅡ反应中心开放部分的比例,将更多的光能用于推动光合电子传递,提高了光合电子传递能力,同时非光化学能量耗散的提高,有助于耗散过剩的激发能,以保护光合机构,缓解环境胁迫对光合作用的影响,体现了小麦叶片的自我保护机制.两个品种相比,长武13的叶绿素荧光参数的变化幅度比陕253小,具有更强的抵御干旱胁迫的能力.     

外源亚精胺对盐胁迫下黄瓜幼苗光合作用的影响

采用营养液栽培,研究了外源亚精胺对50mmol·L-1NaCl胁迫下黄瓜幼苗植株生长、叶片叶绿素含量、光合气体交换参数和叶绿素荧光参数(PSⅡ光化学效率)的影响。结果表明:NaCl胁迫显著降低了黄瓜植株生长量、净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)(P<0.05),但对PSⅡ实际光化学效率(ФPSⅡ)、光化学淬灭(qP)、有效光化学效率(Fv′/Fm′)、非光化学淬灭(qN)和PSⅡ最大光化学效率(Fv/Fm)无显著影响(P>0.05);外源亚精胺显著提高了盐胁迫下黄瓜植株生长量、叶绿素含量、净光合速率、气孔导度、胞间CO2浓度,增加了ФPSⅡ、qP、Fv′/Fm′,降低了qN(P<0.05);外源亚精胺对Fv/Fm影响不显著(P>0.05)。外源施加亚精胺可增强盐胁迫下黄瓜植株的光合能力,主要是由于减弱了盐胁迫对植株的气孔限制,但对PSⅡ实际光化学效率影响较小,且叶面喷施比根施处理对改善盐胁迫下植株的生长和光合作用更有效。     

NaCl胁迫下交替呼吸途径对叶绿素含量及其荧光特性的影响

以菜豆幼苗作为试验材料,分析了NaCl胁迫下交替呼吸对叶绿素含量以及叶绿素荧光特性变化特征的影响,以探讨交替呼吸途径在逆境下的生理学作用以及植物在盐胁迫下光系统Ⅱ(PSⅡ)的调节作用机制。结果表明:(1)随着NaCl胁迫浓度(0、100、200、300mmol/L)的增高,菜豆幼苗叶片叶绿素含量显著下降,叶片光系统Ⅱ(PSⅡ)潜在最大光化学量子效率(Fv/Fm)、光适应下最大光化学效率(Fv′/Fm′)、PSⅡ光适应下实际光化学效率[Y(Ⅱ)]和光化学荧光猝灭(qP)与对照相比均显著性下降,而非光化学猝灭(NPQ)较对照组显著增加,同时交替呼吸容量在NaCl胁迫下也显著上升。(2)与单独NaCl胁迫相比,在NaCl胁迫下施加交替呼吸的抑制剂水杨基氧肟酸(SHAM)会导致菜豆幼苗叶片叶绿素含量、Fv/Fm、Fv′/Fm′、Y(Ⅱ)和qP进一步显著下降、NPQ进一步显著增加。研究认为,NaCl胁迫导致菜豆叶片光系统Ⅱ光化学效率下降和光能耗散增加,交替呼吸途径可有效缓解NaCl胁迫下菜豆叶绿素含量的减少以及光系统Ⅱ光化学反应效率的下降。     

热锻炼对甘蓝幼苗叶片激发能分配的影响

以喜温凉的蔬菜甘蓝为试材,研究了热锻炼与对照甘蓝幼苗叶片光合速率和叶绿素荧光参数对高温胁迫的响应．结果表明,叶片温度在25-35℃之间,热锻炼苗和对照苗叶片叶绿素可变荧光(Ｆv)、光化学猝灭(qP)、非光化学猝灭(qN)、PSⅡ化学效率(ФPSⅡ)没有明显的变化;当叶温高于35℃时。热锻炼苗的Fv、qP和中ФPSⅡ均明显高于对照,37℃时Fv、qP和ФPSⅡ分别比对照高53％、24％和86％;qN较对照低22％,尤其是与光抑制(光破坏)有关的qNs明显降低,以维持较高的高能态猝灭(qNf)耗散过剩激发能。保护PSⅡ反应中心不受破坏。减轻了光抑制,这与热锻炼幼苗叶片在高温下具有较高的光合能力是一致的。     

外源NO对NaCl胁迫下长春花幼苗生物量和叶绿素荧光的影响

在温室条件下采用盆栽法,研究了50mmol·L-1NaCl胁迫下5个不同浓度外源NO供体硝普钠(sodium nitroprusside,SNP)对长春花(Catharanthus roseus)幼苗生物量、叶绿素含量和叶绿素荧光的影响。结果表明:(1)鲜重和干重均在S2(50mmol·L-1NaCl+0.1mmol·L-1SNP)处理下达到最高,分别较对照S0(50mmol·L-1NaCl)显著增加18.8%和13.9%。叶绿素a、叶绿素b和类胡萝卜素与生物量相似,均在S2处理下含量最高,但它们均与S0无显著差异,叶绿素a/b变化较为复杂。(2)0.1mmol·L-1SNP缓解盐胁迫对PSⅡ反应中心的破坏效果最好,显著提高50mmol·L-1NaCl胁迫下长春花幼苗叶片的可变荧光(Fv)、最大荧光(Fm)、PSⅡ最大光化学效率(Fv/Fm)、PSⅡ潜在活性(Fv/Fo)、实际光化学效率(φPSⅡ)和光化学荧光猝灭系数(qP),降低了初始荧光(Fo)、非光化学荧光猝灭系数(qN)。综上所述,0.1mmol·L-1SNP能够通过降低盐胁迫对叶绿素的降解和对PSⅡ反应中心的破坏,促进幼苗生长,提高对50mmol·...     

Paleosols and paleoenvironments of the middle Miocene,Maboko Formation,Kenya

The middle Miocene (15 Ma) Maboko Formation of Maboko Island and Majiwa Bluffs, southwestern Kenya, has yielded abundant fossils of the earliest known cercopithecoid monkey (Victoriapithecus macinnesi), and of a kenyapithecine hominoid (Kenyapithecus africanus), as well as rare proconsuline (Simiolus leakeyorum, cf. Limnopithecus evansi) and oreopithecine apes (Mabokopithecus clarki, M. pickfordi), and galagids (Komba winamensis). Specific habitat preferences can be interpreted from large collections of primate fossils in different kinds of paleosols (pedotypes). Fossiliferous drab-colored paleosols with iron-manganese nodules (Yom pedotype) are like modern soils of seasonally waterlogged depressions (dambo). Their crumb structure and abundant fine root-traces, as well as scattered large calcareous rhizoconcretions indicate former vegetation of seasonally wet, wooded grassland. Other fossiliferous paleosols are evidence of nyika bushland (Ratong), and early-successional riparian woodland (Dhero). No fossils were found in Mogo paleosols interpreted as saline scrub soils. Very shallow calcic horizons (in Yom, Ratong, and Mogo paleosols) and Na-montmorillonite (in Mogo) are evidence of dry paleoclimate (300-500 mm MAP=mean annual precipitation). This is the driest paleoclimate and most open vegetation yet inferred as a habitat for any Kenyan Miocene apes or monkeys. Victoriapithecus was abundant in dambo wooded grassland (Yom) and riparian woodland (Dhero), a distribution like that of modern vervet monkeys. Kenyapithecus ranged through all these paleosols, but was the most common primate in nyika bushland paleosols (Ratong), comparable to baboons and macaques today. Mabokopithecus was virtually restricted to riparian woodland paleosols (Dhero), and Simiolus had a similar, but marginally wider, distribution. Habitat preferences of Mabokopithecus and Simiolus were like those of modern colobus monkeys and mangabeys. A single specimen of Komba was found in dambo wooded grassland paleosol (Yom), a habitat more like that of the living Senegal bushbaby than of rainforest galagids. A shift to non-forest habitats may explain the terrestrial adaptations of Victoriapithecus, basal to the cercopithecid radiation, and of Kenyapithecus, basal to the hominoid radiation. Both taxa are distinct from earlier Miocene arboreal proconsulines, oreopithecines and galagids.     

Astragalar morphology of late Eocene anthropoids from the Fayum Depression (Egypt) and the origin of catarrhine primates

The phylogenetic relationships of the late Eocene anthropoids Catopithecus browni and Proteopithecus sylviae are currently a matter of debate, with opinion divided as to whether these taxa are stem or crown anthropoids. The phylogenetic position of Catopithecus is of particular interest, for, unlike the highly generalized genus Proteopithecus, this taxon shares apomorphic dental and postcranial features with more derived undoubted catarrhines that appear in the same region 1-2 Ma later. If these apomorphies are homologous and Catopithecus is a stem catarrhine, the unique combination of plesiomorphic and apomorphic features preserved in this anthropoid would have important implications for our understanding of the crown anthropoid morphotype and the pattern of morphological character transformations that occurred during the early phases of stem catarrhine evolution.Well-preserved astragali referrable to Proteopithecus, Catopithecus, and the undoubted early Oligocene stem catarrhine Aegyptopithecus have provided additional morphological evidence that allows us to further evaluate competing hypotheses of interrelationships among Eocene-Oligocene Afro-Arabian anthropoids. Qualitative observations and multivariate morphometric analyses reveal that the astragalar morphology of Proteopithecus is very similar to that of early Oligocene parapithecids and living and extinct small-bodied platyrrhines, and strengthens the hypothesis that the morphological pattern shared by these taxa is primitive within crown Anthropoidea. In contrast, Catopithecus departs markedly from the predicted crown anthropoid astragalar morphotype and shares a number of apomorphic features (e.g., deep cotylar fossa, laterally projecting fibular facet, trochlear asymmetry, mediolaterally wide astragalar head) with Aegyptopithecus and Miocene-Recent catarrhines. The evidence from the astragalus complements other independent data from the dentition, humerus and femur of Catopithecus that support this taxon's stem catarrhine status, and we continue to maintain that oligopithecines are stem catarrhines that constitute the sister group of a clade containing propliopithecines and Miocene-Recent catarrhines.     

Stratigraphy, artefact industries and hominid associations for Sterkfontein, member 5

A revised stratigraphy for the early hominid site of Sterkfontein (Gauteng Province, South Africa) reveals a complex distribution of infills in the main excavation area between 2.8 and 1.4 m.y.a, as well as deposits dating to the mid to late Pleistocene. New research now shows that the Member 4 australopithecine breccia (2.8-2.6 Ma) extends further west than was previously thought, while a late phase of Member 4 is recognized in a southern area. The artefact-bearing breccias were defined sedimentologically as Member 5, but one supposed part of these younger breccias, the StW 53 infill, lacks in situ stone tools, although it does appear to post-date 2.6 Ma when artefacts first appear in the archaeological record. The StW 53 hominid, previously referred to Homo habilis, is here argued to be Australopithecus. The first artefact-bearing breccia of Member 5 is the Oldowan Infill, estimated at 2-1.7 Ma. It occupies a restricted distribution in Member 5 east and contains an expedient, flake-based tool industry associated with a few fossils of Paranthropos robustus. An enlarged cave opening subsequently admitted one or more Early Acheulean infills associated in Member 5 west with Homo ergaster. The artefacts attest to a larger site accumulation between ca. 1.7 and 1.4 Ma, with more intensive use of quartzite over quartz and a subtle but important shift to large flakes and heavier-duty tools. The available information on palaeoenvironments is summarized, showing an overall change from tropical to sub-tropical gallery forest, forest fringe and woodland conditions in Member 4 to more open woodland and grassland habitats in the later units, but with suggestions of a wet localized topography in the Paranthropus -bearing Oldowan Infill.     

32种杜鹃花属植物在迁地保育条件下的自交研究

迁地保育条件下的杜鹃花属植物自交可育性一直缺乏系统的比较研究,该文对5亚属13亚组32种杜鹃花属植物的自交进行了数据采集与分析,初步揭示了迁地保育条件下杜鹃花属植物自交育性特征。结果表明:(1)自交可育与不育是杜鹃花属植物有性生殖中的两个并存现象,自交能育型种类或多于不育型。在受试的32种杜鹃花中,自交不育型10种、弱可育型5种、可育型7种、高可育型10种,其中27种的自交育性为首次报道,涵盖包括杜鹃亚属杜鹃组(sect.Rhododendron)和马银花亚属(subgen.Azaleastrum)及常绿杜鹃亚属(subgen.Hymenanthes)中银叶杜鹃亚组(subsect.Argyrophylla)等5个亚组在内的未被研究的类群。(2)通过与自然授粉有关育性指标的比较,发现不同种类的自交可育性指标有大幅度降低及增高这两类截然不同的现象,从而提出了自交可能是部分杜鹃花属植物的适应策略,或者对不利环境及其媒介条件的主动响应。(3)在云锦杜鹃亚组(subsect.Fortunea)这个被认为最原始的杜鹃花类群中,具备从自交不育到高可育的所有类型,并可能由此奠定整个杜鹃花属的遗传基础,而类群与种类分布的不同区域气候环境长期直接的或通过影响传粉媒介间接的作用,则可能是最终塑造该属植物自交育性多样化的外部动力。(4)该文还依据有关自交的研究结果,对杜鹃花属植物的迁地保育、育种、相关学科发展进行了讨论,并认为后合子期败育的理论不能完美地解释自交不能坐果的现象,而多倍体似不会导致自交不育。     

荨麻科三新种

该文描述了荨麻科三新种:(1)自中国重庆市发现的荨麻科荨麻属一新种,城口荨麻。此种与异株荨麻有亲缘关系,区别特征为此种的茎被少数刺毛,叶片多为心形,雄、雌花序均不分枝,瘦果在中央稍凹陷。(2)自中国广西发现的荨麻科赤车属一新种,来宾赤车。此种与特产云南东南部的富宁赤车相近缘,与后者的区别在于本种茎的毛开展或向上弯曲,叶片长椭圆形,基部斜楔形,雌花具3~4枚花被片,其中1~2枚较大花被片在背面顶端具一长筒状突起。(3)自缅甸北部发现的荨麻科楼梯草属一新种,克钦楼梯草。此种在体态上与骤尖楼梯草甚为相似,与后者的区别在于本种的每一茎节具正常叶和一退化叶,托叶狭披针状条形和无脉,雌总苞苞片无角状突起,雌小苞片较大,呈楔状长圆形,雌花具一小花被片,以及雌蕊具一宽倒卵球形柱头。     

利用DNA片段测序方法探究枳属和富民枳的分类地位

富民枳(Poncirus polyandra)属于芸香科(Rutaceae)枳属(Poncirus Raf.)。自发表以来,分类地位一直备受争议,其中在Flora of China中认为富民枳为柑橘杂交种(Poncirus polyandra),把枳属归并于柑橘属(Citrus)。该研究选取枳属的富民枳、枳(Poncirus trifoliata)及柑橘属下8个种共10个种47个个体作为研究材料,以九里香(Murraya exotica)为外类群,利用3个叶绿体片段(trn L-trn F、trn S-trn G、rbc L)、ITS片段和1个单拷贝核基因(Chr 5)数据构建系统发育树,探究枳属和富民枳的分类地位。结果表明:基于3个叶绿体片段数据构建的最大似然树(ML)和贝叶斯树(BI)的拓扑结构基本一致,10个物种聚为两大分支,即柑橘属的8个物种聚为一大分支,富民枳和枳聚为另一大分支。其中,富民枳所有个体聚为一小单系分支,枳的所有个体聚为一小单系分支,支持枳属和富民枳独立存在。2个核DNA片段数据结果显示,枳属的两个种与柑橘属的8个物种聚在一个大分支里,无法确立枳属的单系地位,但富民枳的9个个体聚在一起,暗示富民枳在遗传上是一个独立的类群。综上研究认为,无论是叶绿体DNA数据还是核DNA数据均支持富民枳是一个独立的物种,但核DNA数据不支持枳属成立。     

基于分子证据确认秦岭藤属与驼峰藤属(夹竹桃科)的系统位置

秦岭藤属(Biondia Schltr.)是中国特有属,约13种,驼峰藤属(Merrillanthus Chun & Tsiang)是仅在我国与柬埔寨分布的单种属,目前两个属均被归并到白前属(Vincetoxicum Wolf),由于取样和系统发育分析尚存一些欠缺,因此其系统位置和归属尚需进一步确认。该文使用2个核糖体基因序列片段(ITS、ETS)、5个叶绿体基因序列片段(psbA-trnH、trnG、trnL、trnL-F、trnT-L),以及二者的合并数据,重建娃儿藤亚族(Tylophorinae)(包含属的模式秦岭藤 [B. chinensis Schltr.=V. shaanxiense(Schltr.)Meve & Liede]与驼峰藤 [M. hainanensis Chun & Tsiang=V. hainanense(Chun & Tsiang)Meve, H. H. Kong & Liede])的系统发育树。结果表明:秦岭藤属与驼峰藤属均包含在白前属中,秦岭藤与青龙藤 [B. henryi(Warb.)Tsiang & Li=V. henryi(Warb.)Meve & Liede]互为姐妹类群,并与V. kawaroense Meve & Liede聚为一支,而黑水藤 [B. insignis Tsiang=V. insigne(Tsiang)Meve, H. H. Kong & Liede]在另一分支中(亚热带分支Subtropical Clade); 驼峰藤属与V. cissoides(Blume)Kuntze和V. philippicum Meve, Omlor & Liede聚为一支。核糖体和叶绿体基因数据均支持秦岭藤属与驼峰藤属归并入白前属,但秦岭藤属为多系,尚需收集更多种类和数据合并分析,深入探讨归并后白前属的种间系统关系和位置。     

Reconstructing the history of Campanulaceae with a Bayesian approach to molecular dating and dispersal–vicariance analyses

We reconstruct here the spatial and temporal evolution of the Campanula alliance in order to better understand its evolutionary history. To increase phylogenetic resolution among major groups (Wahlenbergieae–Campanuleae), new sequences from the rbcL region were added to the trnL-F dataset obtained in a previous study. These phylogenies were used to infer ancestral areas and divergence times in Campanula and related genera using a Bayesian approach to molecular dating and dispersal–vicariance analyses that takes into account phylogenetic uncertainty. The new phylogenetic analysis confirms Platycodoneae as the sister group of Wahlenbergieae–Campanuleae, the two last ones inter-graded into a well-supported clade. Biogeographic and dating analyses suggest that Western Asia and the Eastern Mediterranean have played a major role as centers of migration and diversification within the Campanula alliance, probably in relation to the intense orogenic activity that took place in this region during the Late Neogene, and that could have promoted isolation and allopatric speciation within lineages. Diversification rates within several Campanula lineages would have increased at the end of the Miocene, coinciding with the Messinian Stage. Strong selective pressures from climate changes and the expansion of mountainous regions during this period are suggested to explain the adaptation to drought, cold or disturbed environments observed in many Campanula species. Several independent long-distance dispersal events to North America are inferred within the Rapunculus clade, which seem to be related to high ploidy levels.     

毛茛科六新种

该文描述了毛茛科六新种：(1)托里乌头,与阿尔泰乌头近缘,区别为其茎和叶无毛,总状花序极密集,雄蕊花丝多有1或2小齿。(2)门源翠雀花,与大通翠雀花近缘,区别为其茎极短,花序总状,退化雄蕊瓣片不分裂。(3)云台山铁线莲,与裂叶铁线莲近缘,区别为其叶为二回羽状复叶,花较小,雄蕊花丝呈黑色,无脉。(4)黑丝铁线莲,与前种云台山铁线莲在亲缘关系上极为相近,区别为其小叶较小,多呈狭卵形或披针形,聚伞花序也较小,通常只具3花。(5)五台山毛茛,与砾地毛茛相似,区别为其基生叶被柔毛,花瓣蜜槽具鳞片,心皮具短而粗的花柱和小柱头。(6)靖西铁线莲,与宝岛铁线莲在亲缘关系上接近,区别为其茎疏被短柔毛,小叶卵形或狭卵形,不分裂,聚伞花序有1~3花,萼片较大(长1.7~2 cm,宽0.5~0.7 cm)。     

毛茛科五新种

描述了毛茛科五新种:(1)托里乌头,与阿尔泰乌头近缘,区别为其茎和叶无毛,总状花序极密集,雄蕊花丝多有1或2小齿。(2)门源翠雀花,与大通翠雀花近缘,区别为其茎极短,花序总状,退化雄蕊瓣片不分裂。(3)云台山铁线莲,与裂叶铁线莲近缘,区别为其叶为二回羽状复叶,花较小,雄蕊花丝呈黑色,无脉。(4)黑丝铁线莲,与前种云台铁线莲在亲缘关系上极为相近,区别为其小叶较小,多呈狭卵形或披针形,聚伞花序也较小,通常只具3花。(5)五台山毛茛,与砾地毛茛相似,区别为其基生叶被柔毛,花瓣蜜槽具鳞片,心皮具短而粗的花柱和小柱头。